The use of modern communication systems through which to communicate is a necessary aspect of modern society. Many different communication services are regularly effectuated by many different users to effectuate many different types of communication services. Many essential, as well as many other, services are predicated upon the ready availability of, and ready access to, communication systems.
As advancements in communication technologies continue, additional communication services, as well as improvements to existing communication services, shall likely become available. Generally, the advancements in communication technologies provide manners by which to communicate data, communicated to effectuate a communication service, in more efficient manners, or at higher data communication rates, or in manners that better provide for successful delivery of data to a receiving station in spite of adverse communication conditions.
The use of digital communication techniques, for instance, has been made possible as a result of technological advancements in communication technologies. Many modern communication systems utilize digital communication techniques. The use of digital communication techniques provides various advantages. By digitizing data, redundancies in the data are more readily removed, permitting the data to be communicated in more efficient form, free of redundancies. Improved data throughput rates or reduced bandwidth requirements needed to communicate the data are permitted.
A radio communication system is an exemplary type of communication system. Digital communication techniques are regularly utilized in many modern radio communication systems.
A cellular communication system is an exemplary type of radio communication system. While cellular communication systems are constructed to be operable in conformity with any of various operating standards, the cellular communication systems generally include network infrastructures having a plurality of spaced-apart base transceiver stations. The base transceiver stations each define cells, and portable communication stations, carried by users, are generally able to communicate with a base transceiver station in whose cell that the portable communication station is positioned when communications are effectuated.
Several analogous types of wireless communication systems have been implemented, and others have been proposed, to encompass limited areas, for example, areas encompassed by a business office or building structure. So-called micro-cellular networks, private networks, and WLANs (Wireless Local Area Networks) are representative of radio communication systems that are operable, at least in various aspects, in manners analogous to operation of a cellular communication system. Additionally, communication systems that utilize ad hoc networks, i.e., do not utilize a fixed network, are also utilized or undergoing development.
Wireless local area networks are, in some respects, technological extensions of conventional local area networks. That is to say, both conventional local area networks and wireless local area networks generally provide for the communication of packet-formatted data. And, mobile nodes of a wireless local area network are analogous to, and sometimes functionally equivalent to, the fixed nodes of a local area network.
Wireless communication systems, such as the aforementioned wireless local area networks are generally constructed to be operable in conformity with the operating protocols of a selected communication standard. While various promulgated operating standards have achieved widespread adoption, many wireless local area networks are constructed to be operable in conformity with an IEEE 802.11(b), operating specification, or a variant thereof. The IEEE 802.11(b) standard is promulgated by the IEEE, and the operating specification has become a predominant wireless LAN standard pertaining to a commercial 2.4 GHz wireless LAN (Local Area Network) frequency range as well as an unregulated band in the 5 GHz frequency range. The 802.11(b) standard specifies, amongst other things, an over the air interface between a wireless client, e.g., a mobile node, and a base station or access point.
Unlike some other communication systems implemented at other frequency bands, the frequency bands allocated for wireless local area networks are relatively unregulated, permitting their speedy deployment and re-deployment, as needed.
Mobile nodes operable in wireless local area networks are typically constructed to monitor selected frequencies within the allocated frequency bands to detect a wireless local area network within communication range of the mobile node. Access points, or other devices, of a wireless local area network broadcast signals to alert mobile nodes of the wireless local area networks of which the access points, or other devices, form portions.
While a plurality of WLANs might be available to a mobile node when the mobile node is positioned at a particular location, there is generally a preference to attempt to communicate by way of a certain WLAN or certain WLANs of the available WLANs. The WLANs are identified by SSIDs (Service Set Identifiers). An SSID is not necessarily unique to a particular WLAN. For instance, a plurality of WLANs operated by a single operator are sometimes identified by a single SSID. Different ones of the WLANs operated by the single operator might be located at widely disparate locations. The relative preference of a mobile node to communicate with a WLAN, identified by an SSID, might well be dependent upon the location at which the mobile node is positioned when communications are to be effectuated. When the mobile node is positioned in one location, for instance, the WLAN, identified by an SSID, might have a first level of preference. But, when the mobile node is positioned at another location, a WLAN identified by the same SSID might well have a different level of preference.
A single list identifying, in order of preference, WLANs, identified by SSIDs, is therefore an inadequate manner by which to identify through which networks that a mobile node should attempt to communicate.
Additionally, the preferences do not necessarily remain static over extended time periods. For instance, network operators enter into preferred roaming agreements, and in other preferred roaming agreements with some regular occurrence. A static listing of preferences is also inadequate for this reason as the priority of preferences might well change over time.
It is in light of this background information related to WLAN network selection by a mobile node that the significant improvements of the present invention have evolved.